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RSS2022 Vol. 9, No. S2
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2022, 9(S2): 1-5.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.001
Abstract:
Introduction Grouted connections of offshore wind foundation structures exhibit complicated behavior, and in particular, the interaction between grouted material and steel pipe is crucial to the overall performance. Method This paper mainly introduced and analyzed the behavior attribute configuration on the simulation interface of the cohesive model. Cohesive model theory was introduced in terms of cohesive behavior of cohesive model, criteria for interface damage judgment and criteria for interface damage evolution. Based on a typical shearkey-less grouted connection, conventional configuration during modeling and contact configuration of cohesive model were introduced. Result Through analysis, the feasibility of implementing cohesive behavior in the cohesive model in ABAQUS is proven. Conclusion The cohesive model proposed by this paper can simulate the collaborative deformation of steel cylinder wall and grouting body, Mises stress distribution of the steel cylinder wall, Tresca stress distribution of the grouting body and load-displacement curve well.
2022, 9(S2): 6-10.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.002
Abstract:
Introduction Due to the time variability and randomness of load, the fatigue problem of grouted connections in offshore wind power is serious and it is necessary to research into the fatigue performance of grouted connections to ensure its safety operation. Method Based on the finite element numerical model, the Markov load matrix was transformed into the stress at the key position of the grouted connections in this study, and combined with the S-N curve of materials and the linear cumulative damage rule, the fatigue performance of the grouted connections was evaluated. Result The finite element model of grouted connections shows that the cumulative damage of steel materials under axial load is greater than that of grouting materials, but less than the limit of DNV specification. Conclusion This study shows that fatigue failure will not occur in the two materials in the grouted connections under the specific load, the structure of turbine is safe, and the analysis method is effective.
2022, 9(S2): 11-17.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.003
Abstract:
Purpose Guangdong Province is a major consumer of natural gas. Since it is highly dependent on natural gas imports and lacks the right to speak in pricing, the natural gas utilization price has been high for a long time. There is an urgent need to establish a natural gas trading market in Guangdong and develop a benchmark pricing hub with international influence so as to secure the natural gas supply and reduce the natural gas utilization costs. Method Studied the process of natural gas market-oriented reform in Europe and the United States, summarized their experiences, and drew inspiration for the Guangdong natural gas market; analyzed the current natural gas market structure, infrastructure and market-oriented reform in Guangdong; built a natural gas market framework suitable for the actual situation of Guangdong, and proposed the key tasks to promote the construction of a natural gas market. Result The research shows that Guangdong Province has a strong demand for natural gas, diversified supply, complete infrastructure, good marketization foundation, and perfect financial market. It has the basic conditions for building a regional virtual trading hub. A natural gas trading market system with coordinated development of natural gas trading hubs and exchanges can be established by referring to the British NBP and Dutch TTF models. The natural gas trading hub focuses on key tasks of promoting the separation of natural gas transportation services and sales operations, creating a unified scheduling mechanism for the trunk pipeline network, constructing a pipe capacity allocation and shipper system, establishing a calorific value-based measurement system, and building infrastructure information disclosure and pipe capacity trading systems. The natural gas exchange focuses on formulating market trading and operating rules, building a trading information system, and promoting the connection between natural gas spot trading and futures trading as well as the futures varieties. Conclusion The proposed scheme conforms to the actual situation of Guangdong and is operable, which can effectively guide the construction of a natural gas trading market in Guangdong.
2022, 9(S2): 18-23.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.004
Abstract:
Introduction In traditional design engineering, there are two trends in the design and selection of auxiliary equipment of heat engine. One is to put function first and ignore cost; the other is to take low cost as the criterion and ignore the importance of some functions. Both of these two selection methods have certain defects, and the function and cost cannot be considered as a whole to maximize the benefits. With the development of the industry, an increasing emphasis is placed on the cost performance in the process of heat engine equipment selection in design engineering so as to achieve the best function at a reasonable cost. Method In this paper, the theory of value engineering was applied to the design and selection of heat engine equipment, and the function and cost were considered in a unified manner through the formula of value coefficient, so as to realize the optimal heat engine equipment selection scheme. Result Combined with practical cases, this paper has demonstrated the feasibility of applying the theory of value engineering to the selection of heat engine equipment. Conclusion The paper provides a feasible method for realizing the unified demonstration of equipment function and cost in the heat engine equipment selection process of the subsequent power plant design.
2022, 9(S2): 24-30.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.005
Abstract:
Introduction In order to improve the thermal efficiency of the whole plant, reduce the power consumption rate, save land and reduce investment in noise reduction facilities, this paper proposes the application scenario of a new cooling tower in thermal power plants, especially in urban gas turbine power plants. Method Based on the engineering background and the actual application, this paper described the selection of mechanical draft cooling tower, focused on the detailed description of the structure and layout of the typical single-sided air inlet mechanical draft cooling tower and the single-sided air inlet high level water collecting mechanical draft cooling tower, compared the two types of mechanical draft cooling tower in terms of energy consumption, noise control, environmental impact, economical efficiency, etc., and described the advantages and disadvantages of the two types of mechanical ventilation cooling tower on the premise of ensuring the same cooling effect by using the minimum annual total cost method of dynamic economic analysis. Result The comparison results show that the high level water collecting device can have a better application prospect in mechanical draft cooling tower. The high level water collecting device can eliminate most of the water pouring noise and greatly reduce the circulating water pump lift; By providing a variable frequency circulating water pump, it can meet the cooling water demand of generator unit under different working conditions, reduce the power consumption rate and achieve obvious energy saving effect; It is suitable for large back-to-back tower type and can save land. Conclusion The application of the new cooling tower in thermal power plants is feasible, especially in urban gas turbine power plants with land shortage. The adoption of a large high level water collecting mechanical draft cooling tower with back-to-back arrangement can improve the overall operation economy of the generator unit circulating cooling water system, reduce the system energy consumption, save energy and reduce emissions, while taking into account the initial investment of the circulating cooling system and the noise reduction effect in power plants. With the vigorous development and investment of large gas-steam combined cycle generator units in China, the application prospect of large high level water collecting mechanical draft cooling towers is broad.
2022, 9(S2): 31-37.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.006
Abstract:
Introduction In China, waste incineration power plant becomes the mainstream of garbage treatment, and the public and society pay more and more attention to it. In addition to solving the problem of waste incineration power plant through social publicity and education, administrative means and technical measures, a good external image – facade design is one of the effective ways to shorten the distance between waste incineration power plants and the public and dilute the contradiction between them. Method Taking Deyang waste incineration power plant as an example, in the design process, the elements affecting the facade were analyzed, integrated and applied to build a friendly and pleasant building image. Result The article carries on the detailed analysis and comparison in function, style, proportion, decoration, color, material and window. Conclusion Through the facade design of Deyang waste incineration power plant, the characteristics of NIMBY facilities are displayed, more “affinity” elements are given to the building facade, so as to achieve a balance industrialization and publicity.
2022, 9(S2): 38-45.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.007
Abstract:
Introduction Karst development areas face complex and changeable geological problems. This paper aims to reduce the risk of engineering construction in karst development areas. Method Taking a power plant in northern Guangdong as an example, this paper analyzed and compared the results of elastic wave CT detection and drilling detection, discussed the how to use elastic wave CT results to guide the pile foundation design, and provided the key points of pile foundation design. Result The results show that elastic wave CT detection can be used to guide the construction of advance drilling and the judgment of pile foundation bearing stratum. The pile foundation design can be optimized by means of transfer girder and other methods. Conclusion The research results can provide reference for engineering construction in karst development areas.
2022, 9(S2): 46-52.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.008
Abstract:
Introduction Because of the high temperature, high dust content and high corrodibility of the flue gas produced by incinerators, easy damage of the thermocouple for measurement of furnace flue gas temperature, and high maintenance cost. This paper explores ways to improve furnace flue gas temperature measurement. Method Firstly, this paper introduced two advanced furnace flue gas temperature measurement methods based on infrared technology, the principle of infrared temperature measurement and bicolorimetry temperature measurement was analyzed, and then the structure and practical application of infrared and colorimetry temperature measurement device were introduced, and the technical comparison was made in detail. Result The infrared and colorimetric method temperature measurement device can be used for the furnace flue gas temperature measurement of refuse incinerators, and can be used for the combustion optimization of refuse incinerators and the ammonia injection optimization of the SNCR system through further research. Conclusion With the application and promotion of the new measuring device, its reliability and accuracy have been improved and verified, and it has a good application prospect.
2022, 9(S2): 53-58.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.009
Abstract:
Introduction The tippler is a common coal unloading equipment used in railway coal project. The coal unloading equipment under the tippler should be selected based on comprehensive consideration of the system layout, civil conditions and investment. Method Comparative analysis of common coal unloading equipment was carried out on the basis of analyzing the working principles and technical characteristics of different common coal unloading equipment. Result The results show that activation coal feeder has certain advantages in the coal unloading equipment selection under tippler for its unique capability of preventing disheveled coal and slip coal, self-locking ability and good environmental protection performance. With the good environmental protection performance, low operation and maintenance cost and flexible arrangement, the fully enclosed screw-type coal feeder also has certain advantages. Conclusion Both the activation coal feeder with good comprehensive performance and the fully enclosed screw-type coal feeder are applicable when the coal unloading equipment under the tippler is arranged in line. It is recommended to use the fully enclosed screw-type coal feeder as a preference when the coal unloading equipment under the tippler is arranged vertically.
2022, 9(S2): 59-67.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.010
Abstract:
Introduction The applicability of the two schemes is analyzed through the application of planetary gear speed regulation and frequency conversion speed regulation in the energy-saving retrofit of the boiler electric feed pumps regulated by hydrodynamic couplings in the fossil-fuel power station. Method Through the analysis of the energy consumption of the planetary gear speed regulation itself and the practical applications, and the comparison with the actual operation of the frequency conversion speed regulation, from the aspects of safety, applicability, adjustable range and energy saving, this paper discussed whether to use planetary gear speed regulation or frequency conversion speed regulation for energy-saving retrofit of boiler electric feed pumps regulated by hydrodynamic couplings in the fossil-fuel power station. Result In the application, the frequency conversion speed regulation has a higher energy saving rate, wider adjustable range, and adequate safety guarantee, and is more applicable than the planetary gear speed regulation. Conclusion The frequency conversion speed regulation is more suitable for the energy-saving retrofit of the boiler electric feed pumps regulated by hydrodynamic couplings in the thermal power station.
2022, 9(S2): 68-73.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.011
Abstract:
Introduction This paper is aimed to study the wind-induced response of 1000 kV lattice independent lightning protection tower and propose the reasonable value of wind-induced vibration coefficient. Method The wind-induced response of 1000 kV lattice lightning protection tower was analyzed in this paper with the help of finite element software ANSYS based on the Davenport fluctuating wind speed power spectral density function adopted in the Load Code for Building Structures and the structural random vibration theory and frequency domain analysis method. The wind-induced vibration coefficient was compared with that calculated by the simplified formula recommended in the Standard for Design of High-Rising Structures. Result The analysis results show that the overall deformation of the lightning protection tower meets the specification requirements for the class B landform when the basic wind pressure is not greater than 0.60 kN/m2; The wind vibration coefficient value obtained from the simplified formula recommended in the Standard for Design of High-Rising Structures and the recommended value in the Technical Code for the Design of Substation Buildings and Structures are generally smaller than the value obtained from the finite element analysis, so special attention should be paid to it during structural design. Conclusion According to the comparative analysis results of this paper, it is recommended that the wind-induced vibration coefficient can be uniformly taken as 2.20 during the structural design of 1000 kV lattice independent lightning protection tower.
2022, 9(S2): 74-78.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.012
Abstract:
Introduction In the DC power supply system, the cable section is usually selected according to the long-term allowable current-carrying capacity of the cable and the allowable voltage drop of the circuit. However, in actual projects, a larger rated current of the circuit breaker may be selected due to stage difference coordination. In this case, the circuit breaker will not act and will burn the cable when the cable is overloaded or short circuited. On one hand, this paper illustrates this problem with project examples. On the other hand, it tries to find a simple relation between cable and circuit breaker to facilitate engineering design. Method On one hand, the selection of cable and the coordination method of DC circuit breaker were briefly introduced through practical examples; On the other hand, the coordination between cable and circuit breaker was analyzed by means of data fitting and curve analysis. Result A set of engineering practical relations between cable section and rated current of circuit breaker are obtained. Conclusion The engineering practical relations between cable section and rated current of circuit breaker have a wide range of applications, providing reference for cable design of DC system in future projects.
2022, 9(S2): 79-83.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.013
Abstract:
Introduction In order to reduce the land acquisition and cost of valve hall for HVDC converter station, a double-layer shielding cage scheme for valve hall of UHVDC converter station is presented in this paper. Method With the base of successful application of double-layer shielding cage in the ±1100 kV UHVDC Changji-Guquan transmission projects, and relative experiment conducted by China power research institute, the economic comparison of various kinds of shielding cages in valve hall was carried out to verify the economy of this scheme. Result The result shows that the double-layer shielding cage scheme has certain advantages. Conclusion The detailed implementing scheme of the double-layer shielding cage for valve hall in HVDC converter station presented in this paper is successfully applied in one project with popularization value.
2022, 9(S2): 84-89.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.014
Abstract:
Introduction The paper aims to realize constant voltage or constant current microgrid control under different types of load conditions. Method A simple DC microgrid was built by using a microcontroller and other circuit components, a closed-loop PID controller was used to control the circuit, and a Simulink simulation model was built at the same time, and the PID parameters were designed and simulated in advance using the simulation model. It could make the PID parameter setting reasonable, reduced the hidden danger of hardware in the microgrid, and ensured the normal operation of each part of the circuit in the process of hardware construction. Result It can be seen from the experimental data that the output value error can be guaranteed to be less than 2% in terms of constant voltage or constant current output. Conclusion The feasibility of using a microcontroller to control the voltage and current of the microgrid is demonstrated in this paper.
2022, 9(S2): 90-97.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.015
Abstract:
Introduction In order to make the grid-connected power conversion system (PCS) for the energy storage microgrid has the same rotation and excitation characteristics as the synchronous generator, the virtual synchronous generation (VSG) control strategy is proposed in the grid-connected PCS control system for the energy storage microgrid. Method In this paper, in view of the fact that the traditional VSG did not have the low voltage ride through (LVRT) capability, the virtual impedance reactive power control link of VSG was constructed to modify the voltage control input signal in real time and improve the support ability of system transient voltage drop. In order to obtain the amplitude and resistance inductance ratio of virtual impedance, LVRT operating conditions were divided into symmetrical and asymmetrical short-circuit failures of the line, and the positive and negative sequence voltage and current were studied to obtain the virtual impedance parameters. Result In order to verify the performance of the proposed control strategy, simulation is performed using Matlab/Simulink, and the simulation conditions are set as follows: three-phase grounding and single-phase grounding faults occur in the external transmission line of the energy storage microgrid respectively. Conclusion The simulation results show that the introduction of virtual impedance into VSG control system can improve the output voltage of the grid-connected PCS for the energy storage microgrid in case of short circuit, play the role of voltage transient support during LVRT, make the energy storage microgrid has LVRT capability, and provide guidance for practical application.
2022, 9(S2): 98-105.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.016
Abstract:
Introduction Unified object ID has been widely used to assist full-lifecycle management of grid equipment assets. Academic and industrial communities focus on the combination of unified object ID and management systems, but neglect whether the existing object ID can meet requirements or not. Method This paper proposed Grid Geo-coding ID (GGID) coding method for grid equipment that takes into account global uniqueness, security, standardability, compatibility, scalability, efficiency and rationality. The GGID consisted of the key information at the planning, design, construction and O&M stages of grid projects, including spatial location, processing technology, equipment type and timestamp. Result Compared with the existing object ID format, the object ID obtained for all the electrical equipment of the pilot substation using the GGID coding method is easier to be combined with the enterprise resource planning system and the BIM model of the full-life cycle, and it can be linked with the existing code. Conclusion According to test and comparison, GGID meets the requirements as the primary key value of the grid asset management system and database, and can be used to serve for the efficient management of grid equipment assets and the information archiving at all stages of the full-life cycle.
2022, 9(S2): 106-111.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.017
Abstract:
Introduction In order to explore the main control conditions of each member of the transmission tower, this paper calculates the 500kV double circuit tangent tower, summarizes and classifies all kinds of members, and identifies their control conditions, so as to provide reference for the future design of tangent tower. Method This paper introduced the typical operating conditions in tower design. Taking the 500 kV tangent tower as an example, this paper identified the control forms of each member through calculation based on the hanging point load of the tower, and summarized the identification results to find the changes in the law. Result For the hanging point, the operating condition with the maximum load in X direction is 90° strong wind, the operating condition with the maximum load in Y direction is broken line, and the operating condition with the maximum load in Z direction is lifting. The operating condition with the maximum total load is lifting. The normal operating condition controles most of the main members of the tower, and the 60° strong wind directly affects the foundation force. The broken line condition controls most of the cross members of the tower, and the installation condition controls the fewest members. Considerable members of the tower are controlled by the load out of the plane due to the same pressure. These members are mainly the cross members from the lower chord of the upper cross arm to the upper chord of the middle cross arm on the front of the tower, and the cross members below the variable slope, and attention should be paid to these members in the design. Conclusion Tangent tower is featured by great numbe, various models and layout forms of members. In project construction, the members should be optimized according to the design conditions and the control conditions of members.
2022, 9(S2): 112-117.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.018
Abstract:
Introduction Quantitative evaluation for power supply reliability improvement effect of planning projects is guided by secondary indexes. In order to solve the problems that the planning of rural distribution network is lacks , this paper proposes a rapid evaluation method for reliability improvement effect of large-scale rural distribution network planning projects. Method This paper first analyzed the main characteristics of rural distribution network. Then, based on the evaluation requirements of power supply reliability improvement effect of distribution network planning project and a simplified topology, this paper proposed an evaluation method for power supply reliability improvement effect of rural distribution network planning projects. Result The proposed method is compared with the industry standard for reliability evaluation of medium-voltage distribution networks, and the calculation accuracy error is within 11%. Conclusion The proposed method achieves a certain computational accuracy. It can meet the needs of rapid evaluation of reliability improvement effect of large-scale rural distribution network planning projects, and effectively improve the quality of distribution network planning.
2022, 9(S2): 118-122.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.019
Abstract:
Introduction Power transmission and transformation projects are energy projects constructed with key state investment. In order to clarify the economic benefits and expected effects of such projects, it is necessary to carry out an economic evaluation of the entire power transmission and transformation projects. Method This paper took a 500 kV power transmission and transformation project in Guangdong as an example, established an index system for comprehensive evaluation of financial benefits firstly, and then used the fuzzy comprehensive evaluation method to make a comprehensive evaluation of the financial benefits of it. Result Through empirical analysis, it shows that the fuzzy comprehensive evaluation method can effectively evaluate the economic benefits of the power transmission and transformation project. At the same time, the final comprehensive evaluation results of such projects in Guangdong are relatively successful, indicating that its level of financial benefit is good. Conclusion Using the fuzzy comprehensive evaluation method to conduct economic evaluation of power transmission and transformation projects can effectively evaluate whether the projects can produce good economic benefits and whether the investment into the projects can produce good expected return.
2022, 9(S2): 123-130.
doi: 10.16516/j.gedi.issn2095-8676.2022.S2.020
Abstract:
Introduction Under the dual influence of the "3060" carbon peak and neutrality policy and the increasingly fierce competition of the general contracting mode in the energy sector, the digitalization of project management will become the core competitiveness of enterprises, and how to improve the digitalization level of project management will become a key. Method This paper analyzed the necessity of digital transformation in digital economy and project management themselves, summarized the characteristics of current domestic and foreign project management platforms, and analyzed the weaknesses of enterprise level project management platforms in on-site management. On this basis, through the on-site collaborative management system of the general contracting project of a power engineering enterprise in South China, the digital transformation of on-site management of the general contracting project of the energy survey and design enterprise was systematically studied and verified. Result The results show that the system can greatly improve the efficiency of project management and create management value through data. Conclusion Establishing a general contracting project management platform with collaborative management of all parties, structured forms, full coverage of processes and comprehensive application of intelligent statements can vigorously promote the digital transformation of project management.
